It has hitherto been known that spiroxazine compounds have properties to develop colors or lose their colors upon irradiation of light, i.e., the so-called photochromism, and various photochromic photosensitive materials utilizing these compounds have been proposed. For example, Japanese Patent Application (OPI) No. 36284/80 (the term "OPI" herein used means "published unexamined application") which corresponds to U.S. Pat. No. 4,215,010 and 4,342,668, and U.S. Pat. No. 4,342,663 disclose spironaphthoxazine compounds as photochromic compounds. Japanese Patent Publication No. 28892/70 which corresponds to U.S. Pat. No. 3,578,602 discloses photochromic materials containing spironaphthoxazine compounds. Further, Japanese Patent Publication No. 48631/74 which corresponds to U.S. Pat. No. 3,562,172 and Japanese Patent Application (OPI) No. 112880/85 which corresponds to U.S. patent applications Ser. Nos. 548,660 , now abandoned, and 635,696, now U.S. Pat. No. 4,637,698, describe photochromic photosensitive materials comprising a high molecular weight substance having dispersed therein a spiroxazine compound.
In general, photochromic photosensitive materials are obtained by dispersing these spiroxazine compounds in a high molecular weight compound and forming the dispersion into a film.